What is the name of the diacritic

What is the name of the diacritic, such as on the last syllable of "perdon," and the penultimate syllable of "gustaria?"  Gracias!

Magister Britannus

I just called it an accent. That is what I recall from high school.

Yes, it is an accent mark (which is a diacritic), but there must be a name for it.  The French equivalent, for example, is "aigu."  

I, like you, call it an accent, (or acento en español.) But when I do that with the Peruana that I study with she corrects me and calls them tildes. Which to me is this:  ˜.  She calls that an enya. Which makes sense since that is what the mark does to the letter n.

The beginning of this article
http://spanish.about.com/cs/writing/g/diacriticalgl.htm
disputes her assertion, but then goes on to say this:

Also known as: "Diacritic" in English, diacrítico in Spanish. Note that in Spanish, the word tilde can be used to refer to accent marks on vowels as well as the mark of the ñ.

Well, I usually say "acento" as well, but I understand the "proper" name is "acento ortográfico", and some other people I know use "tilde"... I think they're all valid

I tend to use "tilde", but "acento ortografico" sounds fancier to an English speaker! Thanks, marie-rocket-spanish ! I'll definitely use that one:).

I'll stick with "the thingy over the vowel"...

 

 I think people would actually still know what you meant!